Ultimax Cement Manufacturing Corp. et al. v. CTS Cement Manufacturing Corp. et al., No. 2008-1218, -1439 (Fed. Cir. Dec. 3, 2009)

The patentee asserted three patents relating to rapid-hardening, high-strength cement. On summary judgment, the district court held certain claims of the patents indefinite and not infringed, and also held one patent unenforceable due to laches. The patentee appealed. The Federal Circuit overturned the district court´s decision on indefiniteness, non-infringement, and unenforceability. On indefiniteness, the district court found that the asserted claim was indefinite because it contained a typographical error. The district court declined to correct the error because it was not apparent from the face of the patent, even though it may have been clear to one of ordinary skill in the art. The Federal Circuit disagreed, holding that “although courts cannot ‘rewrite claims to correct material errors,’ if the correction is not subject to reasonable debate to one of ordinary skill in the art, namely, through claim language and the specification, and the prosecution history does not suggest a different interpretation, then a court can correct an obvious typographical error.” On infringement, the Federal Circuit found that the district court incorrectly construed one of the claims by “erroneously rel[ying] on expert testimony and a single dictionary definition to the exclusion of other dictionary definitions and, most importantly, the context in which the term was used within the claim and the specification.” Because the claim construction was reversed, the district court´s holding of non-infringement was vacated. On unenforceability, the district court found that a presumption of laches was created because the patentee waited 12 years to file suit after the patent in question issued and the patentee should have known of the alleged infringer´s use of the patented cement at the time of the patent´s issuance. The Federal Circuit held that “the only time relevant to the laches presumption is that after [the patentee] knew or should have known of the allegedly infringing product.” Despite the length of time between the patent´s issuance and the filing of the suit, the Federal Circuit found that genuine issues of fact remained because the claim limitation at issue would not be detectable in the finished product. Therefore, it was not clear that the patentee would have known of the alleged infringement until discovery commenced in the case.

A copy of the opinion can be found here.